71693681 has 2 divisors, whose sum is σ = 71693682. Its totient is φ = 71693680.

The previous prime is 71693663. The next prime is 71693693. The reversal of 71693681 is 18639617.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42706225 + 28987456 = 6535^2 + 5384^2 .

It is a cyclic number.

It is not a de Polignac number, because 71693681 - 2¹⁴ = 71677297 is a prime.

It is a super-2 number, since 2×71693681² = 10279967790659522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (71693651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35846840 + 35846841.

It is an arithmetic number, because the mean of its divisors is an integer number (35846841).

Almost surely, 2^71693681 is an apocalyptic number.

It is an amenable number.

71693681 is a deficient number, since it is larger than the sum of its proper divisors (1).

71693681 is an equidigital number, since it uses as much as digits as its factorization.

71693681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54432, while the sum is 41.

The square root of 71693681 is about 8467.2121149762. The cubic root of 71693681 is about 415.4259544847.

The spelling of 71693681 in words is "seventy-one million, six hundred ninety-three thousand, six hundred eighty-one".